From 4f526ea1891109b3c4d517bb5543a37b3dc759a2 Mon Sep 17 00:00:00 2001
From: Ren Baoshuo <i@baoshuo.ren>
Date: Sun, 3 Jan 2021 14:30:50 +0800
Subject: [PATCH] =?UTF-8?q?P3743=20kotori=E7=9A=84=E8=AE=BE=E5=A4=87?=
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R44571071
---
 Luogu/problem/P3743/P3743.cpp | 40 +++++++++++++++++++++++++++++++++++
 1 file changed, 40 insertions(+)
 create mode 100644 Luogu/problem/P3743/P3743.cpp

diff --git a/Luogu/problem/P3743/P3743.cpp b/Luogu/problem/P3743/P3743.cpp
new file mode 100644
index 00000000..e471c308
--- /dev/null
+++ b/Luogu/problem/P3743/P3743.cpp
@@ -0,0 +1,40 @@
+#include <bits/stdc++.h>
+
+using namespace std;
+
+int n;
+double p, a[100005], b[100005];
+double sum, l, r = 1e10, mid;
+
+bool check(double mid) {
+    double q = mid * p;
+    sum = 0;
+    for (int i = 0; i < n; i++) {
+        if (a[i] * mid > b[i]) {
+            sum += a[i] * mid - b[i];
+        }
+    }
+    return sum <= q;
+}
+
+int main() {
+    cin >> n >> p;
+    for (int i = 0; i < n; i++) {
+        cin >> a[i] >> b[i];
+        sum += a[i];
+    }
+    if (sum <= p) {
+        cout << -1 << endl;
+        return 0;
+    }
+    while (r - l > 1e-6) {
+        mid = (l + r) / 2;
+        if (check(mid)) {
+            l = mid;
+        } else {
+            r = mid;
+        }
+    }
+    cout << fixed << setprecision(10) << l << endl;
+    return 0;
+}